The present invention relates to a visible image forming method, a program, and a visible image forming system for forming a visible image in addition to the data recording on an optical disk.
The optical disk recording apparatus capable of forming the visible image such as the character, the pattern, or the like apart from the essential data recording onto the optical disk such as CD-R (Compact Disc-Recordable), or the like is provided currently. The optical disk recording apparatus of this type optically denatures a part of the unrecorded area by applying the laser beam onto the unrecorded area onto which the data recording was not applied, to thus form the character or the pattern as the visible image (For example, see Non-Patent Literature 1).
Non-Patent Literature 1:
Yamaha Corporation, CD-R/RW product official web site DiscT@2, (online), Heisei 14 August 2, Yamaha Corporation, (Search on Oct. 11, 2002 through Internet)
<URL:http://www.yamaha.co.jp/product/computer/handbook/disc ta2.html>
However, in order to execute the visible image formation in the up-to-date optical disk recording apparatus, the format of the signal used to modulate the laser beam that is applied onto the optical disk at the time of recording the data (for example, EFM modulation signal: Eight To Fourteen Modulated Signal) and the format of the signal used to modulate the laser beam that is applied onto the optical disk at the time of forming the visible image are different. Therefore, the signal processing circuit used in the data recording and the signal processing circuit used in the visible image formation must be provided respectively. For this reason, a scale of the signal processing circuit must be enlarged, a control LSI must be newly designed/manufactured, and a control program must be largely varied.
The data-recording signal processing circuit in the up-to-date optical disk recording apparatus is designed to make possible the high-speed transfer processing by using the parallel processing. Now, if further the visible-image recording signal processing circuit is similarly constructed such that the processing circuit can deal with the high-speed transfer processing, there existed not only the problem such that the overall circuit scale is expanded but also the problem such that the wirings are complicated. In contrast, if the visible-image forming signal processing circuit is designed as the serial processing type, there existed the problem such that the visible image formation is delayed.
In the related art, the data writing system is constructed as the CLV data writing system having the constant linear velocity. Therefore, it is difficult to realize the polar coordinate system that permits such writing system to form the visible image with good precision.